As black pigments, there have been conventionally used carbon black, perylene-based pigments and the like. Among these black pigments, carbon black has been most widely used because of its high tinctorial strength as well as an excellent blackness, an excellent acid resistance and an excellent weather fastness. However, carbon black has a very small particle size and a large bulk density and, therefore, tends to suffer from problems such as poor handling property and workability. Also, it may be difficult to use such carbon black in applications requiring a high electrical resistance, such as black matrix materials for liquid crystal color filters, because of a low electrical resistance thereof. Further, the carbon black may contain carcinogenic polycyclic condensation compounds and, therefore, has a problem concerning a safety.
Although the perylene-based pigments extensively used as fast pigments exhibit red-violet-brown-black colors in a solid state, the color tone thereof is not necessarily kept thermally stable (W. Herbst & K. Hunger “Industrial Organic Pigments”, VCH Press, pp. 467–480).
An object of the present invention is to provide a black perylene-based pigment exhibiting an excellent blackness, an excellent heat resistance and an excellent weather fastness as well as a high safety, which is usable as black matrix pigments for liquid crystal color filters.